1. Field of the Invention
The present invention relates to a method of manufacturing a laser diode device used, e.g., for industrial equipment, etc.
2. Background Art
Japanese Laid-Open Patent Publication No. 2009-71162 discloses a technique for splitting or cleaving a semiconductor laser bar along the desired planes into individual laser diode devices. In this technique, first, separation trenches are formed in a semiconductor laser bar so as to extend across the entire transverse dimension of the semiconductor laser bar, thereby forming mesa stripes. The semiconductor laser bar is then cleaved by causing crack propagation from grooves which have been scribed in the semiconductor laser bar along the separation trenches.
It should be noted that such scribing is achieved by means of a pointed tool, such as a diamond needle, which, however, cannot be stabbed into the edge portions of the semiconductor laser bar. As a result, the semiconductor laser bar must be cleaved without scribed grooves in the edge portions thereof. In this case, it has been found that the resulting cleaved surfaces sometimes have cracks or chippings of considerable magnitude, resulting in reduced yield. Especially in some cases, the crack propagation is such that the resulting cleaved surfaces extend to a mesa stripe, also resulting in reduced yield.